<!DOCTYPE html>
<html>
<head>
<script type='text/javascript'
src="https://datejs.googlecode.com/files/date.js"></script>
<script type='text/javascript'>
console.log(Date.today().addDays(-10));
console.log(Date.today().addDays(-10).toString());
</script>
</head>
<body>
</body>
</html>